Random bleeding?

I am a little confused so many you all can give me some ideas or something.

DH and I had an early miscarriage Dec. 10th. We decided to not prevent but not try until next month but when we have been having sex it's unprotected. We have done it like... 6 times since the MC? Something like that. Anyways on the 26th I started spotting and figured it was my period coming back. Funny thing is it was very light and it was gone within a few hours. I have never had implantation bleeding but if we conceived right after the MC I would be able to get a positive yet I haven't. What else could that random spotting be?

It's probably too early to get a positive right now. It could be implantation bleeding, but it could also be the start of your period. My cycles changed after each miscarriage. After the last one, I would spot for several days before actually starting my period.